Counting relay system



Mm 25, 1947. F, s, EAD 2,4fi7,831

COUNTING RELAY SYSTEM Original Filed Nov. 7, 1942 aw as QC QU as aw QU as as nwavme DECEASED, 5y

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ATTORNEY Patented Mar. 25, 1947 UNiTED STATES. PATENT FFlCE-'-" confirms. RELAY SYSTEM Fullerton S. Kinkead, deceased, late of New York, N. Y., by Rita Smith Kinkead, administratnx, Trudeau, N. Y., assignor to Bell 'ielephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Original application November 7, 1942, Serial No;

464,:s46. Divided and this application September s, 1943, Serial No. 501,125

16 Claims. (Cl. 177-353) This invention relates to relay systems and particularly to counting relay chains.

This application is a division of copending ap; plication Serial No. 464,846, filed November 7; 1942, by F. S. Kinkead and G. A. Locke, which has issued as Patent 2,407,286 granted September 10, 1946.

An object of the invention is to provide. a counting relay chain capable of counting forwardly and backwardly.

Another object of the invention is to provide a two-way counting relay chain capable of reversing'qthe direction of countingat any point in a counting cycle and proceeding with the counting operation in the reverse direction.

The invention features a set of counting relays for counting upwardly or downwardly between 0 and 9. Specifically, the set consists of eight relays so interrelated that at all times a minimum of two relays are energized and under some circumstances three relays are energized. This interrelation of the relays provides for the preparation of a sequential circuit path on either side of a path which is at the time effective, so that the direction of counting may reverse at any time and proceed in such reverse direction.

In accordance with the preferred embodiment of the invention a controller for the counting relay chain in the nature of a potential divider has six fixed potential points which are connected to the first six contacts of a ten-contact switch bank and has four of the six points connected to the remaining four contacts of the contact bank. A pair of voltage supply conductors extends from the ends of the potential divider to a source of direct current electrical potential. The switch arm of the ten-contact point switch is connected to the control electrodes of fiveelectron discharge devices.

A potential divider having fixed potential points is connected across the source of potential, and the cathodes of the electron discharge tubes are connected to the several fixed potential points so that the tubes have progressively greater negative bias. Since the control electrodes of all of the tubes receive like potentials over the switch arm conductor from any contact of the switch, none, one or more of the tubes will be rendered conductive depending upon the instantaneous value of the control electrode potential of the tubes relative to their progressively different cathode potentials. From no tubes to five tubes may be rendered conductive thus providing six selective conditions for the first six contacts of the switch. The remaining fourcontacts of the may be ten lamps eacn of which has one terminal connected in common to one terminal of a source of electrical potential and has the other terminal connected to an individual lamp conductor.

Referring to the set'of' discharge tube controlled relays, counting relays, and individual lamp conductors, one lamp conductor is electrified directly under the control of the discharge tube controlled relays when none of those relays is energized, one lamp conductor is electrified directly under the control of those relays when all five of the relays of the set are energized and the remaining eight lamp conductors become electrified selectively through paths prepared by the eight counting relays. Only one lamp conductor may be electrified at any instant and thus only one lamp will be lighted at any instant.

. Referring again to the set of counting relays, the relays thereof areso interrelated that at all times a minimum .of two relays are energized and under some circumstances three relays ar energized. Specifically, when none of the elect on discharge tube controlled relays is energized .the first and last counting relays of the set are energized. When all of the discharge tube controlled relays are energized, the fourth and fifth counting relays are energized. Under certain other conditions of the discharge tube cont'rolled relays, which conditions are with one or four relays energized, two of the counting relays are simultaneously energized. With the remaining possible conditions, namely, two or three of the discharge .tube controlled relays energized, three of the discharge tubes for the last four contacts of the switch duplicate four of the first six contacts of the switch. These conditions are represented by acitivation of one, two, three or four of the electron discharge tubes and energization of the corresponding relays which they control. For these four conditions, only one of which may exist.at any instant, either the first four counting relays or the last four counting relays control electrification of their associated individual lamp conductors, the two subsets of four counting relays being operably effective alternately as the counting operation progresses in either direction. With the foregoing arrangement, during one traversal of the controlling switch contacts by the contact arm, the counting relays will go through a complete cycle and will sequentially electrify the ten individual lamp conductors.

For a complete understanding of the invention reference may be had to the following detailed description to be interpreted in the light of the accompanying drawing consisting of a single figure which is a circuit diagram showing the preferred embodiment of the counting relay chain and a system for controlling it.

Referring now to the drawing, the reference numeral 23 designates a double-ended switch arm which wipes across 'a bank of contacts 24, of which there are teniarranged in slightly less than a semicircle. Thus,*for each half revolution of switch arm 23, it will traverse the ten contacts of contact bank 24. The two ends of the switch arm 23 cannot engage the end contacts of contact bank 24 simultaneously, there being an offset equal to the mounting centers of the contacts.

Associated with the contact bank 24 is a potential divider 4| which may comprise a single resistor winding having a plurality of taps or may comprise a plurality of individual resistors serially connected. From the terminals of potential divider 4| conductors 42 and 43 extend to a battery, as will be described later. The individual contacts of the bank 24 have been designated to 9, inclusive, and it will benoted that the end terminals of potential divider 4| are connected ,to the terminals 8 and 5 of bank 24. The four tap terminals of potential divider 4| are connected to contacts 2, 3 and 4 and also to contacts 8, 1, 8 and 9 of switch bank 24,

A conductor 44 extends from switch arm 23 to the control electrodes or grids of five electron discharge tubes 5|, 52, 53, 54 and 55. A potential divider comprising serially-connected resistors 66, 81, 68, 69, 10 and 1| is connected between conductors 42 and 43. A battery 12 or other source of direct current potential has its negative terminal connected through a resistor 13 to conductor 42 and has its positive terminal connected through resistors 14, 16, 11 ands1'8 to conductor 43. Assuming that the conductors 42 and 43 have .negligible resistance substantially the same potential will be impressed across potential divider 4| as is impressed across the potential divider comprising resistors 66 to 1|, inclusive. The

cathode of tube 5| is connected to the junction of resistors 66 and 61 so that the cathode is more positive'than conductor 42 and the upper terminal of potential divider 4| by the potential difference across resistor 66. The cathode of tube 52 is connected to the junction of resistors 61 and 88 so that the cathode of the tube will be more positive than that of tube 5| by the potential difference across resistor 61 and will be more positive than the potential of conductor 42 by the total potential diiierence across resistors 66 and 61.

Similarly, the cathode of tube 53 is connected to the Junction of resistors 88 and 89, the cathode of tube 54 is connected to the junction of resisters 69 and 13 and the cathode of tube 55 is connected to the junction of resistors 18 and 1| so that the cathode of each tube is progressively more positive than the tube preceding it. Conductor 43 is more positive than the cathode of tube 55 by the potential difference across resistor 1|.

The anode of tube 5| is connected through the upper winding of an electrically biased relay8| to the junction of resistors 10 and 1|. Thus the anode of tube 5| is more positive than the cathode by the total potential difference across resistors 61, 68, 69 and 10, diminished by the potential difference, if any, across the winding of relay 8|. The operating winding of relay 8| stands as a load device in relation to .tube 5|. Resistors 51,88,89 and 10 taken together represent the anode voltage source for the tube 5|, since they are part of a potential divider connected across the power supply. When the tube 5|, or any other of the tubes is passing current of insignificant magnitude under the control of its grid, the potential difierence across the winding of relay BI, and other relays in relation to other tubes, will be similarly insignificant in magnitude and in the case of tube 5| the potential of its anode relative to its cathode may be considered as substantially equal to the potential difference across resistors 61, B8, 69, and 10. The anode of tube 52 is connected through the upper winding of electrically biased relay 82 to the junction of resistors 1| arid 18 which affords a higher positive potential for the anode of tube 52 than the cathode of that tube has. Similarly, the anodes of tubes 53, 54 and 55 are connected through the upper windings of relays 83, 84 and 85, respectively, to the junctions of resistors 18 and 11, 11 andlfi, and 16 and 14, respectively. The biasing windings of relays 8| to 85 are connected in series with resistors 13 and 14 across battery 12. i

The several resistive sections of potential divider 4| are so proportioned and the potential differences across resistors 66, 81, 68, 69 and 10 are such that when switch arm 23 engages the zero contact of bank 24 none of the tubes 5| to 55 will pass suflicient anode current to operate any of the relays 8| to 85., When switch arm 23 engages the contact of bank 24 the. grids of tubes 5| to 55 will be made less negative with respect to their cathodes and tube 5| will be rendered sufliciently conductive to operate relay 8|. When switch arm 23 engages contact 2 of bank 24 tube 52 will be rendered suificiently conductive to operate relay 82, tube 5| remaining conductive becauseits grid is made still less negative with respect to its cathode. As switch arm 23 engages contacts 3, 4 and 5 of bank 24 in succession, tubes 53, 54 and 55 will be rendered conductive in succession to operate relays 83, 84 and 85, respectively, so that when the switch arm engages contact 5 all of the tubes 5| to 55 will be conductive and all of the relays 8| to 85 will be operated. When switch arm 23 moves into engagement with contact 6 of bank 24 the grids of tubes 5| to 55 will be reduced to the same potential that they had when the switch arm engaged contact and tubes 52 to 55 will be cut off, leaving only tube 5| conductive and only relay 8| operated. As switch arm 23 successively engages contacts 1, 8 and 9 of bank 24, tubes 52, 53 and 54 will be rendered conductive in succes- 'minal of which is connected to ground. The leftsion and relays 82, 83 and 84 will again be operated. As switch arm 23 moves out of engagement with contact 9 of bank 24 and into engagement with the zero contact all of the tubes to 55 are cut oil or are rendered insuificiently con- 5 ductive to operate the relays 8| to 85, inclusive, so that the armatures of these relays are restored to their left-hand contacts. From the foregoing it will be apparent that tubes 5| to 55, inclusive, are all cut off only when switch arm 23 engages the zero contact and are all conductive only when the switch arm engages contact 5. Tubes 5| to 54 are rendered conductive in succession as switch arm 23 traverses contacts I to 4, inclusive, and again as the switch arm traverses contacts 6 to 9, inclusive.

It should be noted with reference to the electron discharge tubes that the particular contact engaged by the switch arm determines the number of tubes that are rendered conductive and that none of the tubes is dependent for its operation upon the operationof another of the tubes so that the switch arm 23 may be operated in either direction and tubes will be successively rendered conductive or successively cut oil in the reverse direction depending solely upon the direction of rotation of the switch. i

The armature of relay 85 is connected to the positive terminal of battery 86, the negative terhand contact of relay 85 is connected to the ar-. mature of relay 84, the left-hand-contact of re-' lay 84 is connected to the armature of relay 83, the left-hand contact of relay 83 is connected to the armature of relay 82, and the left-handcontact of relay 82 is connected to the armature of relay 8|. The left-hand contact of relay BI is connected over individual lamp conductor 81 to one terminal of a left-handalamp of a group of ten lamps 88. The other terminal of the lefthand one of the lamps 88 and one terminal of each of the other lamps is connected to the negative terminal of battery 90, the positive terminal of which is grounded; Thus, with none of the tubes 5| to 55 conductive and none of the relays 8| to 85 operated, a path will be established from the positive terminal of battery, 86 over conductor 81 and through the left-hand one of the lamps 88 to the negative terminal of battery 9|l a nd the lamp will be lighted.

'Tlfia right-lfand contact of relay 85 is connected by individual lamp conductor 89 to one terminal of the sixth lamp 88, counting from the left. With switch arm 23 engaging contact 5 of bank 24 all of the tubes 5| to 55 will be conductive, all of the relays 8| to 85 will be operated, and a circuit will be completed from battery 86 over the right-hand contact f relay 85, conductor 89, the sixth lamp in the bank counting from the left to battery 99 on the other terminal and the lamp will be lighted. It will be noted that the two conditions for the lighting of the two lamps identified in this paragraph and the preceding paragraph effect the control of the lamps directly through the relays 8| to "85.

The right-hand contacts of the four relays 8|,82, 83 and 84 are connected by conductors III, H2, H3 and H4, respectively, to the arm tures of four counting relays H6, H1, H8 and H9. These contacts are also connected through 70 branching conductors |2|, I22, I23 and I24, respectively, to the armatures of four additional counting relays I26, I21, I28 and I29. Each of the relays II6 to H9, inclusive, and I26 to I29, inclusive, is a biased polar relay having three op- 75 fect of the biasing winding and will cause the single armature to engage the single front contact.

Assuming that the system is in operation and that switch arm 23 is engaging the zero contact of bank 24, as shown, none ,of the relays 8| to will be energized and a circuit may be traced from the positive terminal of battery 86, through the armatures and left-hand contacts of the relays 8| to 85, serially, conductor 81, branching conductor I3I, the second operating winding of counting relay I29,.conductor I32, the third operating winding of counting relay II6, resistor I33 and conductor I34 to the negative terminal of battery I36, the positive termi al of which is connected to ground. Relays |I and I29 will thus be energized, overcoming the effect of the biasing windings and operating their armatures to the single front contacts. Battery I36 and battery having like polar connections, the lamps 88 cannot become operated over unintentional or sneak conductive paths, such as' the one from battery 99, the extreme left-hand lamp 88, conductors 81 and I3I, second winding of relay I29, conductor I32, third winding of relay H6, and

resistor I33 to battery I36. Individual lamp conductors I4I, I42, I43 and I44 extend from the front contacts of relays 6 to I I9, inclusive, to one terminal of each of the second, third, fourth and fifth of the lamps 88 counting from the left. Similarly, individual lamp conductors I46, I41, I48 and I49 extend from the front contacts of relays I26 to I29, inclusive, to one terminal of each of the seventh, eighth, ninth and tenth of the lamps 88. Although relays H6 and I29 may be assumed to be energized at this time, as previously stated, conductive paths are not extended through their armatures to the second and tenth lamps, respectively, because the armatures of relays 8| and 84 are out of engagement with their right-hand contacts from which conductive paths extend to the armatures of relays H6 and I29, respectively. None of the relays H1, H8, H9,

H26, I21 and I28 will be energized at this time.

p One operating winding of each of the counting relays II8 to H9 and I26 to I29 is shunted by a condenser I50 for the purpose of imparting a slow release characteristic to each relay. The condensers have been shown connected inshunt with the third operating winding of each relay. It makes no difierence which operating winding is shunted by a condenser, as the magnetic field produced by the cessation of current through any one of the operating windings of these relays will induce, in the winding which is shunted by the condenser, current which flows to charge the condenser, and the armature will be held while this charging current exceeds the biasing current.

7 Upon movement of the switch arm 23 from the zero contact to the contact I of bank 24, tube 5| becomes conductive and relay 9| operates its armature to the right-hand contact. In leaving the left-hand contact the armature of re1ay'8l interrupts the previously traced circuit to the extreme left-hand lamp 88 and also interrupts the previously traced circuit through the second winding of relay I29 and through the third winding of relay H6. These'relays hold for a short interval, due to their shunting condensers I50, and maintain conductive paths through their armatures and front contacts. At its right-hand contact relay 8i completes a circuit over conductor III, the armature and front contact of relay I I6 and over conductor I 4i to the second lamp 88 which lights. The relay also completes a circuit over conductor III and through the armature and front contact of relay H6, first winding of thatrelay, third winding of relay I I1, resistor I and conductor I34 to the negative terminal of battery I36, over which circuit relay H6 remains operated and relay H I becomes operated. Since no circuit is completed through an operating winding of relay I29, that relay releases after its characteristic delay interval.

When the switch arm 23 is advanced to the contact 2 of switch bank 24, tube 52 becomes conductive, tube 5I remaining conductive, and relay 82 operates, relay 8| remaining operated. At its left-hand contact relay 82 interrupts the circuit through the armature of relay 8I and conductor III so that the second lamp 88 is extinguished and the circuit through the first winding of relay H6 and the third winding of relay I I1 is interrupted. At its right-hand contact the relay 82 completes a circuit over conductor H2, armature and front contact of relay H1 and conductor M2 to the third lamp, which lights, and

also through'the first Winding of relay HI, second winding of relay H6, third winding of relay H8, resistor I52 and conductor I34 to the negative terminal of battery I 36 whereby relay H8 becomes energizedand relay I I6 is held energized along with relay H'I.

When the switch arm 23 is moved to contact 3 of bank 24, tube 53 will be rendered conductive and relay 83 will be operated. At its left-hand contact relay 83 interrupts a circuit over conductor-H2 and the armature and front contact of relay Hi to the third lamp from the left and also interrupts the circuit through the first winding of relay 'I H, the second winding of relay I I6 and the third winding of relay I I8. At its righthand contact the relay 83 completes a circuit over conductor H3 and the armature and front contact of relay I I 8 and over conductor I 43 to the fourth lamp from the left, which lights. A circuit is also completed from the front contact of relay H8 through the first winding ofthat relay, second winding of relay H1, third winding of relay H9, resistor I53 and conductor I34 to the negative terminal of battery I36 so that relays H1 and H8. remain energized, relay I I9 becomes energized and relay I16 is released.

When the switch arm 23 is advanced to the next contact of bank 24 which is contact 4, tube 54 will be activated and relay 84 will be energized to release the circuit over which relays I ll, H8 and I [9 have been held operated and also to open the circuit of the fourth lamp, and to complete the circuit for the fifth lamp over conductor I I4, armature and front contact of relay I I 9 and conductor I44, and also to complete a circuit through the armature and front contact of relay I I9, first winding of that relay, second winding of relay H8, resistor I54 and conductor I34 to the negative terminal of battery I36. It will be noted that in this condition of the apparatus only two of the counting relays, namely, the relays H8 and H9, are energized, whereas when only the relays H8 were energized and when only the relays 8i,

82 and 83 were energized the relays H1, H8 and H9 were energized. The reason for this is that in the next step of the switch arm 23 and the energization of the final relay in the series 8I to 85, the circuit of the sixth lamp will be completed directly over conductor 89 from the right-hand contact of relay 85 as previously described and not through the armature and front contactof one of the counting relays, andit is not necessary for the relay I I9, when completing its holding circuit through its armature and front contact, to prepare a path for the operation of the next lamp by energizing the next counting relay.

Suppose now that the direction of rotation of switch arm 23 had been reversed and instead of advancing to the contact 4 it had gone from contact 3 back to contact 2 of bank 24. Under this circumstance tube 54 would not have been activated and tube 53 would-have been cut oil, releasing relay 83 and leaving only tubes 5| and 52 conductive. The armature of relay 83 upon moving out of engagement with its right-hand contact interrupts the circuit of the fourth lamp 88 and also interrupts the circuit through the first winding of relay H8, the second winding of relay II! and the third winding of relay H9. The armature of relay 83 in returning to the left-hand contact completes acircuit from the positive terminal of battery 86 through the armature and right-hand contact of relay 82, conductor I I2, armature and front contact of relay Ill, and conductor I42 for the third lamp and also through the armature and front contact of relay II'I, first winding of that of switch arm 23 in the reverse direction to the contact I of bank 24. It will be, apparent from this that the counting relay circuit is arranged to count in either direction by the preparatory energization of counting relays on either side of a counting relay through which a lamp is being operated, in anticipation of the necessity for completing the circuit of a lamp through either one of the prepared relays. In the case of the operation of a lamp through the armature and front contact of relay I I9 there is no occasion for preparatorily energizing a relay beyond it because the conductor 99 stands in lieu of a counting relay and is always prepared to operate the sixth lamp counting from the left, the circuit being completed solely by operatiomof the relay 85.

Assuming again clockwise movement of arm 23, from contact 4 to contact 5, relay 85 is operated,

and in addition to connecting positive battery to the sixth lamp, it also completes a circuit through the second winding of relay H9, third winding of relay I26, resistor I56 and'conductor I34 to battery I36 to hold relay H9 and to operate relay I26 in preparation for movement of switch arm 23 either to contact 4 or to contact 6 of bank 24. Under this condition only two of the counting relays are energized, which satisfies the 8I to 85 are concerned, the duplication involving cutting ofi of tubes 52 to 55 and releasing relays 82 to 85. Relay H6 is at this time unoperated so that no circuit is Completed through its armature and front contact, and a lamp operating circuit is traced through conductor III from the righthand contact of relay 8|, branching conductor I2I, armature and front contact of relay I26 and conductor I46 to the seventh lamp. ,Also a circuit is completed through the armature and front contact of relay I25, first winding of that relay, third winding of relay I21, resistor I'I, conductor I34 and battery I36 so that relay I2'I becomes preparatorily energized and relay I26 remains energized. Only two of the counting relays are required to be energized at this time because in the event that the switch arm 23 is moved back to contact 5, the sixth lamp will be operated over conductor 89 without any preparational operation.

As the switch arm 23 is advanced to contact I the next lamp, namely, the eighth lamp is operated, relays I26 and I2'I are held energized through their second and first windings respectively and relay I 28 is preparatorily energized through its third winding and resistor I58. When the switch arm steps to contact 8, the next or ninth lamp is energ zed, relay I25 is released and relay I29 is preparatorily energized through its third winding and resistor I59.

When the switch arm is moved to contact 9, the last contact in the bank, which movement is evidenced by activation of all of the tubes except tube 55, the circuit of the tenth or extreme righthand lamp is completed over conductor I49, relays I28 and I 29 are held energized through their second and first windings, respectively, and resistor I60, and relay I2! is released. This is again a condition under which only two of the counting relays are energized. The reason for this is that when switch arm I23 advances another step in the same direction it will leave contact 9 and engage the zero contact, thus cutting off all of the tubes 5| to 55 and completing a conductive path from battery 86 to the first or extreme left-hand lamp over conductor 81 which stands in lieu of a'counting relay and requires no counting relay preparation.

Assuming that the switch arm 23 advances through this additional step, thus returning to the point of beginning, all of the relays 8| to 85 are released so. that the circuit through the armature and front contact and first Winding of relay I29 and second winding of relay I28 is interrupted. However, a circuit is completed which was traced as part of the initial condition including conductors 81 and I 3|, second winding of relay I29, conductor I32, third winding of relay I I6, resistor I33 and conductor I34 to battery I36 so that relay I29 will be held energized and relay I IE will be preparatorily energized. Under this condition only two of the counting relays are energized and these occupy sequential positions on either side of conductor 81 so that the preparational conditions for operation of the extreme right-hand lamp or the second lamp from the left are satisfied.

Although a specific embodiment of the invention' has been shown in the drawings and described in the foregoing specification, it will be understood that the invention is not limited to such specific embodiment but is capable of modification and rearrangement, and substitution of parts and. elements without departing from the lays are prepared by said first-mentioned relay to count "backwardly and forwardly from said first-=mentioned relay.

2. In a counting relay system, a relay having an armature and front contact and a holding winding energizable through said armature and front contact, and second and thirdrelays having preceding and succeeding sequential counting relation to said first-mentioned relay and each having a winding energizable in series with the holding winding of said first-mentioned relay, whereby said second and third relays are prepared by said first-mentioned relay to count backwardly or forwardly from said first-mentioned relay.

3. In an electrical distributor system, a plurality of distribution paths including some permanently established and others requiring preparatory establishment, means controlled from each of said permanently establishedlpaths for.

preparatorily establishing two of said other paths having preceding and succeeding sequential relation to said permanently established paths, means controlled over either of said sequentially preceding and succeeding paths for preparatorily establishing an adjacent path in sequential direction away from the permanantly established path, and means controlled from each such adjacent paths for preparatorily establishing two paths having preceding and succeeding sequentialrelation thereto, whereby said distributor system always has three consecutive distribution paths in prepared state and is capable of distributing in either direction from the middle one of said three paths.

4. In an electrical distributor system, first and second permanently established distribution paths, a plurality of distribution paths having sequential dispositions intermediate said first and second permanently established paths, a plurality of distribution paths having sequential dis-. position intermediate said second and first per-' manently established paths, each of said intermediate paths including means operable to preparatorily establish said paths, means controlled from each of said permanently established paths for operating the path establishing means in the two intermediate paths immediately adjacent to said permanently established paths, means controlled from each of said immediately adjacent paths for operating the path establishing means in the next intermediate path in sequential direction away from its adjacent permanentlyestablished path, and means controlled from each other intermediate path including said next intermediate path for operati g the path establishing means in the two pat s immediately adjacentthereto, whereby said distributor system always has three consecutive distribution paths in established condition and is capable of distributing in either direction from the middle one of said three paths.

5. In an electrical distributor system, a plurality of sequentially related and functionally coordinate distribution paths of which a small percentage are permanently prepared and the remainder are preliminarily preparable, means for completing said paths individually in succession times prepared.

6. In an electrical distributor system, a plurality of sequentially related and functionally coordinate distribution paths of which a small percentage are permanently prepared and the remainder are preliminarily preparable, said permanently prepared paths being uniformly interspersed among said preliminarily preparable paths,- means for completing said paths individual y in succession in either sequential direction, and means controlled from any path upon completion thereof for preparing a minimum of one and a maximum of two of said preliminarily preparable paths whereby two distribution paths in sequential juxtaposition to any completed pat are at all times prepared.

7. In an electrical distributor system, a plurality of distribution paths of which a small percentage are permanently prepared and the remainder are preliminarily preparabe, and means controllable over said distribution paths and interassoc ated with each other and with said permanently prepared paths in a closed ring pattern for preparing a minimum of one and a maximum of two of said preliminarily preparable paths whereby a minimum of two distribution paths in sequential juxtaposition to any completed path are at all times prepared.

8. In an electrical distributor system, a plurality of distribution paths of which a small percentage are permanent y prepared and the remainder are preliminarily preparable, said permanently prepared paths being uniformly intersoersed among said pre iminary preparable paths, and means controllable over said distribution paths and interassociated with each other and-with said permanently prepared paths in a closed ring pattern for preparing a minimum of one and a maximum of two of said preliminarily preparable paths whereby a minimum of two distribution paths in sequential juxtaposition to any completed path are at all times prepared.

9. In an electrical distributor system, a series of relays each having an armature and front contact, a plurality of distribution control paths having sequential distributing relation each connected to the armature of one of said relays. a local holding winding and an operating winding for a minimum of one and a maximum of two adjacent relays connected to the front contact of each relay, at least one additional distribution control path, an operating winding of each of two of said relays connected to said additional distribution control path, said additional distriburelays having operating windings connected to said additional distribution control path are at opposite ends of said series of relays and the bridging relation of said additional distribution control path aflords continuous distribution in repetitious cycles in either sequential direction among said distribution control paths.

11. In an electrical distributor system, at least two series of relays each having an armature and front contact, a plurality of distribution control paths having sequential distributing relation, each path being connected to the armature of a relay in each series, a local holding winding and an operating winding of a minimum of one and a maximum of two relays in the same series connected to the front contact of each relay, at least one additional distribution control path, and a connection from an operating winding of an end relay of one series and from an operating winding of the non-corresponding end relay of the other series to said additional distribution control path, whereby said additional distribution control path has distributive bridging relation to the distribution control paths connected to the armatures of the specified end relays of the two series and aifords progressive distribution in either direction between said distributively bridged distribution control paths.

12. A system according to claim 11 in which the distribution control paths having connections to the armatures of the relays in the two series are adapted to control the relays of the two se-.

ries in succession.

13. In an electrical distributor system, at least two series of relays each having an armature and front contact, a plurality of distribution control paths having sequential distributing relation, each path being connected to the armature of a relay in each series, a local holding winding and an operating winding of a, minimum, of one and a maximum of two relays in the same series connected to the front contact of each relay, additional control paths equal in number to the num ber of sets of relays, and connections from an operating winding of an end relay of one series and from an operating winding of a non-corresponding end relay of another series to each of said additional, distribution control paths whereby said additional distribution control paths have distributive bridging relation to the distribution control paths connected to the armatures of the end relays having operating windings connected to said additional distribution control paths and afford progressive distribution in repetitious cycles in either sequential direction among said distribution control paths.

14. In an electrical distributor system, a plurality of distribution paths having sequential distributive relation and adapted to be completed individually, a plurality of relays adapted to prepare said distribution paths, said relays each having opera ing windings connected to two of said paths and each such connection including operating windings of two of said relays for operating the relays to prepare their distribution paths, and means for completing said paths successively in either sequential direction.

15. In an electrical distributor system, a plura ity of distribution paths having sequential distributive relation and adapted to be completed individually, a plurality of relays adapted to prepare said distribution paths, said relays each having operating windings connected to the two of said paths sequentially juxtaposed to the path controlled by the particular relay and each such connection including operating windings 6f the two relays controlling the paths sequentially juxtaposed to the particular path for operating the relays to prepare their respective distribution paths, and means for completing said paths in either sequential direction.

16. In a counting relay system, a relay having an armature and front contact and a holding winding energizable through said armature and front contact, second and third relays having like armatures and front contacts and holding windings and having operatin windings preparatorily energizable through the armature and front contact of said first-mentioned relay, a work circuit connected to each of said front contacts, and means for completing the holding winding circuit and work circuit of said first-mentioned relay and the energizing winding circuit of said second and third relays and adapted to complete the holdin windin circuit and work circuit of either of said preparatorily energized second and third relays, whereby to count in either direction from said first-mentioned relay and the work circuit associated therewith.

. RITA SMITH KINKEAD, Administratrz'a: of the estate of Fullerton S.

Kinkead, Deceased.

REFERENCES CITED The following references are of record in the 10 file of this patent:

UNITED STATES PATENTS Number 

